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Aluminium Extraction and uses
• Aluminium is extracted from the mineral bauxite which is an oxide of Aluminium. Bauxite deposits in India are usually associated with laterites and occur as “blankets” or “cappings” at high plateaus. However, at Katni in Jabalpur district of M.P., and in coastal tracts of Gujarat and Goa, there are low level deposits. Bauxite occurs widely in India but major reserves are in Bihar, Maharashtra, M.P., Orissa, Gujarat, Karnataka, T.N., Goa and U.P.
• Aluminium metal is extracted from bauxite by the electrolytic process. Hence this industry depends on availability of cheap and abundant power.
• Aluminium is used by the electrical industry in place of the more expensive copper wherever possible. About 50% of Aluminium production is consumed by this sector.
• Other uses are for making utensils, in transport, packing, building and construction industries. Aluminium furniture is preferred for its light weight and better finish.
• Leguminous crops are those whose growth rejuvenates the soil. These plants belong to the legume family, characterised by irregular sweet-pea shaped flowers.
• Leguminous plants have the capacity to synthesise atmospheric nitrogen and return it to the soil, thereby increasing its fertility.
• Another advantage is that they are generally drought resistant and do not require large quantities of water for cultivation.
• The most important leguminous crops in India are pulses and oilseeds. Pulses are rotated with other crops like sugarcane and rice to maintain soil fertility.
• The more important pulses are gram and pigeon pea (or tuvar). Gram and black gram are grown in Rajasthan, Uttar Pradesh, Haryana, Madhya Pradesh and Punjab. Pigeon Pea is largely produced in Uttar Pradesh, Madhya Pradesh and Maharashtra. Bihar, Karnataka, Gujarat, Tamil Nadu and Andhra Pradesh also grow small quantities of tuvar. Recently the International Crop Research Institute for Semi-Arid Tropics (INCRISAT) has developed a variety of pigeon pea with high yield and drought resistance.
Cause and Low productivity and its remedy
• The low productivity of Indian agriculture is mainly due to loss of fertility in the soil due to continuous cultivation without allowing for steps such as fallowing, etc., which helped to restore fertility in the past.
• This has also caused marginal land to be cultivated extensively which has low productivity. Agricultural organisation is also poor due to fragmented holdings, low investments, insufficient irrigation, lack of proper credit and marketing facilities.
• The seeds used are also of poor quality. Increased salinity, alkalinity and acidity of soil, coupled with high price of chemical fertilizers are also contributing factors.
• The steps for improving the position include restoration of land fertility by encouraging use of chemical fertilizers or organic manures, provision of improved variety of seeds, improved land tenure systems to avoid fragmentation, provision of extended irrigation facilities, introducing modern marketing techniques and provision of timely credit. All steps to encourage optimal use of land have to be introduced.
Advantages and disadvantages of farm mechanisation in India
• Farm mechanisation is necessary to improve the productivity of land and of the agricultural worker. It is an essential step for commercialisation of agriculture and changing the age old subsistence character of Indian farming.
• However, in the Indian environment where there is surplus labour and chronic unemployment in the agricultural sector, farm mechanisation is not welcomed by some. It is argued that it would displace labour and aggravate inequalities in income and wealth in the rural sector. It is also contended that improvements in production could also be achieved by employing more labour thereby also reducing unemployment.
• The arguments are not well founded. There is a case against total and complete mechanisation of agriculture as in Western countries. Such mechanisation may disturb the basic balance in agricultural organisation.
• But semi-mechanisation(like introduction of pumps, tractors, harvestors, etc), has the following advantages:
(1) Reduction in the overall cost of operation with a positive cost/benefit ratio.
(2) Timely completion of agricultural operation.
(3) Possibilities of economic multiple cropping.
(4) Making maintenance of farm animals unnecessary for agricultural operation.
• Although mechanisation is limited by the topography and size of land holdings, it is definitely useful for raising the backward Indian agriculture. It is not possible to improve the productivity of marginal lands by simply increasing the number of workers. The fear of unemployment is also exaggerated as intensive cultivation by mechanisation will increase demand and generate employment.
Important problems faced in Command Area Development (CAD)
• The Command Area Development Programmes (CADP) were intended to bridge the gap between irrigation potential created by various projects and the actual use of that water for irrigation. The Cultivable Command Area (CCA) was classified into major and minor sources and steps taken for better management of land and water resources in the cultivable command areas.
• It was found that the major drawbacks encountered in the use of irrigation potential were due to waterlogging and salinity. Before irrigation projects were taken up on large scale, the problem was that vast quantities of water during monsoon months flowed away to the sea, thus depriving the land of much needed water. When major irrigation projects resulted in the storage and release of adequate quantities for agricultural operations, the problem of waterlogging in certain areas came to the forefront.
• Waterlogging occurs due to the topography and hinders cultivation particularly of such crops as do not require water throughout the period of their growth. It is prevented by scientific drainage schemes to take away excess water. Salinity is due to the presence of sodium, calcium and magnesium salts in the soil which render it infertile. The injurious salts are confined to the top soil.
• The salt impregnated soils can be rectified by effective drainage system to dissolve saline salts in the top soil. Vigorous action is being taken to improve the performance of Cultivable Command Area Project by tackling waterlogging and salinity.
Prospects of bringing fallow land under cultivation
• Wasteland is of two kinds (1) cultivable and (2) non-cultivable. The former has the potential for being activated but is lying fallow for various reasons like waterlogging, salinity, soil erosion, nonavailability of water, deforestation, unfavourable physiography, etc. Non-cultivable waste lands are barren and cannot be put to any use such as agriculture, forestry, etc., e.g. snow-covered areas of the Himalayan regions, barren deserts of Rajasthan.
• The extent of wasteland in India is approximately 53.3 million hectares. The largest wasteland areas are in Jammu and Kashmir and Rajasthan and comprise nearly 50% of the total wastelands of India. The Kashmir wastelands cannot be cultivated at all whereas Rajasthan wastelands can be brought under the plough if suitable inputs are made available. Cultivable wastelands can be recovered if the reasons which caused them to become fallow are removed.
• Some of the ways in which this can be achieved are:
→ Proper and effective drainage of water-logged areas.
→ Removal of salinity of soil by irrigating top soil for dissolving sodium, calcium and magnesium salts.
→ Major irrigation efforts like the Indira Gandhi canal to water the desert areas of Rajasthan.
→ Steps to prevent soil erosion like bunding, terracing, contour ploughing, levelling of uneven land, etc.
→ Large areas of cultivable wastelands in U.P. and Gujarat suffer from salinity caused by over-irrigation and many areas in Assam, Western and Eastern and Eastern Ghat, and Tamil Nadu have become wasteland due to deforestation.